Update from 2.10 to 3.3. Getting now the same Fatal Error msg, Front and Backend

[Rama]

Finally got around to update 2.10.x to 3.3 with Live update.
It all looked good and login in to the backend it said its running in mx mode and safe mode.
None of my extensions seemed to be compatible with 3.3, didn't want to delete any.
I disabled safe mode and maintenance mode and now I am stuck with this message on the Frontend side and Backend:

Warning: in_array() expects parameter 2 to be array, null given in system/modules/core/library/Contao/System.php on line 142
#0 [internal function]: __error(2, 'in_array() expe...', '/home6/swaskicl...', 142, Array)
#1 system/modules/core/library/Contao/System.php(142): in_array('getInstance', NULL)
#2 system/modules/core/library/Contao/System.php(322): Contao\System::importStatic('registration_in...')
#3 system/modules/core/pages/PageRegular.php(41): Contao\System::loadLanguageFile('default')
#4 index.php(263): Contao\PageRegular->generate(Object(Contao\PageModel), true)
#5 index.php(447): Index->run()
#6 {main}

Fatal error: Class 'registration_info_mailer' not found in /home6/swaskicl/public_html/system/modules/core/library/Contao/System.php on line 142

Even trying to start the install.php gives me the same msg.
Besides overriding everything with a backup I made back to 2.10.x, any other idea how this could be fixed?
Pete

[xchs]

Hi Rama,

seems like the extension "registration_info_mailer" is causing the error. Actually, the aforementioned extension is compatible with Contao 3.3.x (see https://packagist.org/packages/menat...on_info_mailer). However, you'd have to get it over the new dependency and package manager "Composer". Just install the Composer client from the extension catalog (or extension manager): https://contao.org/en/extension-list...mposer.en.html

[Rama]

Hi Rama,

seems like the extension "registration_info_mailer" is causing the error. Actually, the aforementioned extension is compatible with Contao 3.3.x (see https://packagist.org/packages/menat...on_info_mailer). However, you'd have to get it over the new dependency and package manager "Composer". Just install the Composer client from the extension catalog (or extension manager): https://contao.org/en/extension-list...mposer.en.html

Thx for the quick answer.
I saw the composer option towards the end of the upgrade process, but didn't want to change too many things at a time.
Besides going back to 2.10.x with my backup and start the upgrade fresh, is there anyway I could fix this, even though I can't get into my backoffice at all right now and use the extension manager?

[Rama]

I restored from a backup. Deleted the "registration_info_mailer" extension and at the end of a new update choose the "Composer".
Was again in Maintence and Safe mode. My site only showed #No layout specified", so I disabled Maintenance mode first with no change to the website and then disabled the "Save mode" after which I got the following message, again for the Front and Back end.

Warning: in_array() expects parameter 2 to be array, null given in system/modules/core/library/Contao/System.php on line 122
#0 [internal function]: __error(2, 'in_array() expe...', '/home6/swaskicl...', 122, Array)
#1 system/modules/core/library/Contao/System.php(122): in_array('getInstance', NULL)
#2 system/modules/core/classes/BackendTemplate.php(44): Contao\System->import('ValumsHelper')
#3 system/modules/core/classes/BackendTemplate.php(108): Contao\BackendTemplate->parse()
#4 contao/index.php(121): Contao\BackendTemplate->output()
#5 contao/index.php(130): Index->run()
#6 {main}

Fatal error: Class 'ValumsHelper' not found in /home6/swaskicl/public_html/system/modules/core/library/Contao/System.php on line 122

Again, any way to fix this without restoring and starting from scratch again?